Lone planets make it just like stars

By Marcus Chown

PLANETS can be spawned by the same process that makes stars, say astronomers who have discovered a developing planet floating alone in a stellar nursery. “It’s a planet but it has all the hallmarks of an embryonic star,” says Jane Greaves of the Royal Observatory in Edinburgh (ROE).

Until recently, it was thought that planets could only build up, or “accrete”, from gas and dust swirling in a disc around a newborn star. But everything changed in 2000 with the discovery of isolated planets without parent stars in the Sigma Orionis star cluster. “Their existence strongly suggested there was another way of making planets,” says Greaves.

Now, Greaves and ROE colleague Wayne Holland, together with Marc Pound of the University of Maryland at College Park, have looked at the Rho Ophiuchus B star-forming region, which is 500 light years away, only one-third as far from us as the famous

To continue reading this premium article, subscribe for unlimited access.